BAGHDAD — Seven Iraqi civilians were killed near the western city of Falluja on Wednesday during an early morning raid conducted by American and Iraqi security forces, officials said.

Four of the dead were brothers between the ages of 12 and 23, according to the Iraqi police and residents of the area. The United States military in Iraq said in an e-mail Wednesday afternoon that the Iraqi military had “planned and led” the “joint counterterrorism” operation. The raid underscored the continuing presence of American service members in security operations, even after the United States declared an official end to the combat at the end of August. An American military spokesman directed inquiries to the government of Iraq.

It is not clear whether the dead were the targets of the raid or how they were killed. Four other people were wounded during the operation.

Officials in Iraq’s Ministry of Defense and in the prime minister’s office did not immediately return calls seeking comment.

Iraqi police said that the raid started about 1 a.m. Wednesday in the village of Hay Jibel, about 40 miles west of Baghdad in Anbar Province.

American helicopters provided support, police officials said, speaking on the condition of anonymity because they were not authorized to speak to the press. The operation concluded about 7 a.m.

Qasim Mohammed Abed, the governor of Anbar Province, said he had been angered by how the raid was conducted and blamed both the American and Iraqi militaries for the deaths.

“We did not know about this operation — they only informed us that there was going to be a small raid in which they would arrest someone,” he said. “We did not expect this to happen.”

Mr. Abed said he had been told by witnesses that the deaths were unjustified.

“The security forces behaved without morals,” the governor said. “They say that people there resisted them, but it is not true. No one resisted them. They just came to bring trouble to this province.”

In the northern city of Mosul on Wednesday, nine Iraqi soldiers were killed and seven other people were wounded after the minibus carrying them struck a roadside bomb, the Iraqi police said.